Ahead of a Boston book launch, Rick Riordan and Mark Oshiro talk gods, monsters, and mythical underwear.
September 23, 2025 | 9:59 AM
7 minutes to read
It started with a joke about underwear. A minotaur’s tighty-whities, to be exact.
The result is a page-turning adventure with humor and heart.
In May 2023, Boston’s Rick Riordan, award-winning New York Times-best-selling author and creator of the “Percy Jackson and the Olympians” empire, was on tour with Mark Oshiro, the award-winning New York Times-best-selling author of middle grade and YA fiction — and Percy Jackson fan.
They’d just collaborated on a Percy Jackson spin-off, “The Sun and The Star.”
Oshiro tells me in our recent Zoom that at one reading, “Rick made a joke while we were sound-checking: Where did the Minotaur get his tighty-whities from? What if he knits them himself?”
The Minotaur in Riordan’s “Jackson” series, Asterion, notably wears bright white Fruit of the Looms.
“My eyes lit up. I was like, ‘I don’t know what it means, but that’s a good idea,’” Oshiro says. “Within a couple months, I sent along a pitch that was like, “Heeeey, so I’ve been thinking about the minotaur for a long time…”
The ball got rolling on a sequel exploring how we think of monsters.
That sequel “The Court of the Dead,” hits shelves Sept 23, and the co-authors are kicking off a book tour at Boston’s Back Bay Events Center at 7 p.m. (Tickets start at $50 and include an autographed book.)
Twenty years ago, “The Lightning Thief” about a demigod named Percy, and based on Greek and Roman myths, rocketed Riordan to the Mount Olympus of middle-grade readers’ favorite authors.
The former middle school teacher has other great middle-grade fantasy series (I love his Boston-set “Magnus Chase and the Gods of Asgard“) and has also launched his own imprint with Disney-Hyperion, “Rick Riordan Presents,” with a goal to “publish great middle grade authors from underrepresented cultures and backgrounds.”
Meanwhile, season 2 of Disney+ series “Percy Jackson and the Olympians” releases Dec. 10 — and season 3 is already filming.
When I interviewed Riordan two years ago, he and Oshiro had just released the first Percy spin-off about Nico, the son of Hades, and his boyfriend Will, the son of Apollo.
Riordan told me then that he wrote the book “50/50 with Mark Oshiro, a great queer author… It was important to me to have that authenticity, to make sure it was representing an experience that I personally do not have, but that is so important to so many kids.”
Now “Court of the Dead” sees Nico and Will joining Nico’s half-sister Hazel at Camp Jupiter. After Nico and Will show the monsters that they don’t have to be evil, some sought refuge at Camp Jupiter. But a mysterious dark force is at work to punish the monsters for their past crimes.
And yes, the hand-knit underwear makes an appearance early on. They write, “Beneath the kilt, Asterion wore a pair of hand-knit tighty-whities… ‘Asterion!’ Hazel cried. ‘Please have some modesty!’
‘Hmph.’ The bull-man planted his fists at his sides… ‘Look at this stitchwork. Look at this continental purling!…This is the same pair I wore when I first fought Percy Jackson, but he said nothing about my stitchwork. Nothing.”
Showing readers the human side of the monster – one who likes to knit, who cares about the stitchwork on his undies, no less – is a fascinating germ.
Asterion then sighs and gets to the crux of the message, complaining that he doesn’t like the term monsters: “We prefer mythics. The term monsters… is rather… loaded. Ever since we were first called that, we were given no choice but to be monsters… We were used. Manipulated.”
I got on a call with the co-authors to talk gods, monsters, co-writing, what’s next for Percy Jackson — and mythological underwear.
This is your second book about Nico and Will. How did your collaboration first start?
Riordan: A book about Nico and his boyfriend wasn’t something I felt I had the right toolbox to tackle myself. Fortunately, Mark was into the [co-writing] idea. We had so much fun the first time that the second book grew organically.
Oshiro: We’re not master-plan people. “Court of the Dead” genuinely came from that joke Rick made about the tighty-whities. Within a couple months, I sent along a pitch: “What if it’s about rethinking what monsters are?” Rethinking monsters was just a really compelling idea.
You didn’t plan for two books.
Oshiro: No! “Sun” had a fairly definitive end. I don’t know what would’ve happened if Rick hadn’t made that joke.
Riordan: I hadn’t thought that far ahead, honestly. I don’t do much long-term planning. This second book was a project of enthusiasm.
Mark, were you a fan of the Percy series before getting involved?
Oshiro: If I was in my office right now, I’d pull out my giant box-sets that I did pull out in my very first meeting with Rick.
Riordan: [laughs]
Oshiro: I came into this very much loving the series. Which also made for intimidating work, because I wanted to do it justice.
What was your introduction?
Oshiro: I was going on my first book tour in 2018. I said to a friend at Disney,“I need something fun to read [to ease] the stress.” They were like, “Have you ever read the Percy Jackson series?” And I was like, “That’s too many books. I need one book.” And they were like, “How dare you, that’s rude.”
[laughs]
Oshiro: They convinced me. I read “The Lightning Thief” in one sitting. In two weeks, I read 14 books. I was supposed to do other work. I didn’t. I read the books. It became, like, a tenth of my personality.
Riordan: [laughs]
That’s awesome. Rick, did you know Mark’s work before?
Riordan: I did. “Anger is a Gift” was my introduction. Loved it. One thing I’ve learned from working with Mark: how to give characters a chance to be self-reflective, to think about how their feelings are evolving, to process, and just doing what humans need to do.
Oshiro: It’s been surreal to write for this series, and also to be given the creative freedom from Rick to write a Mark Oshiro book. Our processes are intertwined to the point where we can’t remember who wrote certain lines.
So how does the co-writing process work?
Riordan: We work off the same document, but not simultaneously. It’s like a conversation. Mark will do the outline, for instance, then I’ll add to that. Mark did the first draft for “Court of the Dead,” I did the second. But they layer over one another.
Do you plot together beforehand?
Oshiro: We’re both outliners. We sent this outline back and forth. That being said, the outline is not a cemented plan. I remember getting that second draft back from Rick and feeling: 70% of this is different and, oh my god — I never thought of that. I would’ve never thought to add this! So it’s that [element of] two minds meeting, and each of them thinks of story and canon slightly differently.
Will we see these Nico and Will books as a TV series at some point?
Oshiro: [claps hands] Oh, please please.
Riordan: [laughs] That would be cool. I don’t know. For one thing, if it’s chronological in Percy’s world, would you need to do all 16 books that come first before the Nico and Will books? I don’t know. There’s a lot that would have to be considered.
What are you hoping kids get from these two spin-off books?
Oshiro: Good question. With both books, I’d like to think — as dark and chaotic as they can get — they’re about compassion. Having compassion for other people.
In the first book, it’s Will and Nico learning to have compassion for each other. In this book, it’s asking what if we have compassion for people and creatures who don’t look like us? Who don’t behave like us, who actually do very strange things sometimes? What if what we learned years ago is not that helpful anymore?
I love that. Rick, what about you?
Riordan: I agree. As always, I hope they simply have a great time and learn reading can be fun. Also, I hope kids feel seen and valued. There’s something very powerful about reading a book and thinking: “Hey, I went through that,” or “Wow, that’s my experience.”
Have you gotten feedback from kids saying that about the first book?
Oshiro: Oh, yeah. I visit middle and high schools quite frequently and it’s been surreal. Especially for young queer kids, or kids who are questioning, or may be in the closet, to get to read about these two characters who ultimately get to be themselves. God, it’s just the most rewarding feeling in the world.
I bet. Rick, what about you?
Riordan: I don’t do school-visits often — which breaks my heart as a former teacher — but I’ve gotten tons of feedback, and the way the readership has embraced the books and Mark is just wonderful to see.
Rick, you’ve told me your background before: You were a middle school teacher, and started telling “Percy” as a bedtime story for your son. Mark, tell me about you.
Oshiro: I’m unhinged.
[laughs]
Riordan: [laughs]
Oshiro: Here’s how my work is described: I either write the most traumatizing thing you’ve ever read — my YA books — or I write deranged Pixar movies — my middle-grade books.
[laughs] OK.
Oshiro: What’s cool about getting to be a part of this project — I never felt I had to not be me. I never felt I had to be a filtered version of myself. I’m so excited for the tour because I have so much fun sitting in chairs uncomfortably, meeting Percy Jackson fans — the funniest people on the planet.
That’s awesome. Rick, anything you want to add about the TV series?
Riordan: We’re filming Season 3 now, and it’s really fun to talk about Nico D’Angelo because he was recently cast for Season 3 [Levi Chrisopulos]. I just got back from watching him do his first days of filming. It’s really exciting.
How do you like the show so far?
Riordan: I’ve been involved since the very beginning. Everything you see has gone through me, and I think it’s going great and getting even better.
Interview has been edited and condensed. Lauren Daley can be reached at [email protected]. She tweets @laurendaley1, and Instagram at @laurendaley1. Read more stories on Facebook here.
Lauren Daley is a longtime culture journalist. As a regular contributor to Boston.com, she interviews A-list musicians, actors, authors and other major artists.
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